x86: zImage: pass device tree setup data to the kernel

On x86 platforms, U-Boot does not provide Device Tree data to the kernel.
This prevents the kernel from using the same hardware description.

Make a copy of DTB data with setup_data header and insert new item into the the setup data linked list.

Signed-off-by Ivan Gorinov <[email protected]>

---
 arch/x86/include/asm/bootparam.h |  1 +
 arch/x86/lib/zimage.c            | 32
++++++++++++++++++++++++++++++++
 2 files changed, 33 insertions(+)

arch/x86/include/asm/bootparam.h +1 -0

index 90768a9..ea25cf7 100644
@@ -12,6 +12,7 @@
 /* setup data types */
 #define SETUP_NONE			0
 #define SETUP_E820_EXT			1
+#define SETUP_DTB			2
 
 /* extensible setup data list node */
 struct setup_data {

arch/x86/lib/zimage.c +31 -0

index 2a82bc8..41ad4c7 100644
@@ -14,6 +14,8 @@
  */
 
 #include <common.h>
+#include <malloc.h>
+#include <asm/global_data.h>
 #include <asm/acpi_table.h>
 #include <asm/io.h>
 #include <asm/ptrace.h>

@@ -95,6 +97,35 @@ static int get_boot_protocol(struct setup_header
 *hdr)
 	}
 }
 
+static int setup_device_tree(struct setup_header *hdr)
+{
+	const void *fdt_blob = gd->fdt_blob;
+	struct setup_data *sd;
+	int size;
+
+	if (!fdt_blob)
+		return 0;
+
+	size = fdt_totalsize(fdt_blob);
+	if (size < 0)
+		return -EINVAL;
+
+	size += sizeof(struct setup_data);
+	sd = (struct setup_data *)malloc(size);
+	if (!sd) {
+		printf("Not enough memory for DTB setup data\n");
+		return -ENOMEM;
+	}
+
+	sd->next = hdr->setup_data;
+	sd->type = SETUP_DTB;
+	sd->len = fdt_totalsize(fdt_blob);
+	memcpy(sd->data, fdt_blob, sd->len);
+	hdr->setup_data = (unsigned long)sd;
+
+	return 0;
+}
+
 struct boot_params *load_zimage(char *image, unsigned long
 kernel_size,

arch/x86/lib/zimage.c +1 -0

 				ulong *load_addressp)
 {

@@ -262,6 +293,7 @@ int setup_zimage(struct boot_params *setup_base,
 char *cmd_line, int auto_boot,
 #endif
 
 	setup_video(&setup_base->screen_info);
+	setup_device_tree(hdr);
 
 	return 0;

}

Quoted 6 lines · Ivan Gorinov

On x86 platforms, U-Boot does not provide Device Tree data to the kernel.
This prevents the kernel from using the same hardware description.

Make a copy of DTB data with setup_data header and insert new item into the the setup data linked list.

So, now is the question, what to do with x86 hardware that has DTS in U-
Boot, but uses ACPI tables, generated by U-Boot.

Would it work properly?

I would try to test it on Intel Edison (I hope you may do this yourself
as well), though I don't know when, have not much time to work with Edison right now.

arch/x86/lib/zimage.c line 19

Quoted 5 lines

#include <common.h>

arch/x86/lib/zimage.c +2 -0

+#include <malloc.h>
 
+#include <asm/global_data.h>
 #include <asm/acpi_table.h>

On x86 platforms, U-Boot does not provide Device Tree data to the kernel. This prevents the kernel from using the same hardware description.

Make a copy of DTB data with setup_data header and insert new item into the the setup data linked list.

Signed-off-by Ivan Gorinov <[email protected]>

---
 arch/x86/include/asm/bootparam.h |  1 +
 arch/x86/lib/zimage.c            | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 33 insertions(+)

arch/x86/include/asm/bootparam.h +0 -0

 /* extensible setup data list node */
 struct setup_data {

arch/x86/lib/zimage.c +32 -1

index 2a82bc8..41ad4c7 100644
@@ -14,6 +14,8 @@
  */
 
 #include <common.h>
+#include <malloc.h>
+#include <asm/global_data.h>
 #include <asm/acpi_table.h>
 #include <asm/io.h>
 #include <asm/ptrace.h>

@@ -95,6 +97,35 @@ static int get_boot_protocol(struct setup_header *hdr)
        }
 }
 
+static int setup_device_tree(struct setup_header *hdr)
+{
+       const void *fdt_blob = gd->fdt_blob;
+       struct setup_data *sd;
+       int size;
+
+       if (!fdt_blob)
+               return 0;
+
+       size = fdt_totalsize(fdt_blob);
+       if (size < 0)
+               return -EINVAL;
+
+       size += sizeof(struct setup_data);
+       sd = (struct setup_data *)malloc(size);
+       if (!sd) {
+               printf("Not enough memory for DTB setup data\n");
+               return -ENOMEM;
+       }
+
+       sd->next = hdr->setup_data;
+       sd->type = SETUP_DTB;
+       sd->len = fdt_totalsize(fdt_blob);
+       memcpy(sd->data, fdt_blob, sd->len);
+       hdr->setup_data = (unsigned long)sd;
+
+       return 0;
+}
+
 struct boot_params *load_zimage(char *image, unsigned long kernel_size,
                                ulong *load_addressp)
 {

@@ -262,6 +293,7 @@ int setup_zimage(struct boot_params *setup_base, char *cmd_line, int auto_boot,
 #endif
 
        setup_video(&setup_base->screen_info);
+       setup_device_tree(hdr);
 
        return 0;
 }
--

2.7.4

On x86 platforms, U-Boot does not provide Device Tree data to the

Quoted 5 lines

kernel.
This prevents the kernel from using the same hardware description.

Make a copy of DTB data with setup_data header and insert new item into the the setup data linked list.

So, now is the question, what to do with x86 hardware that has DTS in U- Boot, but uses ACPI tables, generated by U-Boot.

Would it work properly?

I would try to test it on Intel Edison (I hope you may do this yourself as well), though I don't know when, have not much time to work with Edison right now.

Quoted 7 lines · Andy Shevchenko

On x86 platforms, U-Boot does not provide Device Tree data to the

Quoted 5 lines

kernel.
This prevents the kernel from using the same hardware description.

Make a copy of DTB data with setup_data header and insert new item into the the setup data linked list.

Quoted 5 lines

So, now is the question, what to do with x86 hardware that has DTS in U-
Boot, but uses ACPI tables, generated by U-Boot.

Would it work properly?

It will work because CONFIG_OF is disabled in most x86 kernel configurations.

Quoted 4 lines

I would try to test it on Intel Edison (I hope you may do this yourself
as well), though I don't know when, have not much time to work with Edison right now.

I am going to try that on a Minnowboard.